D26303: Remove endl in qDebug as it's already add "\n" + port to Qt::endl in qt5.15

[Laurent Montel]

mlaurent added a reviewer: dfaure.

REPOSITORY
  R309 KService

REVISION DETAIL
  https://phabricator.kde.org/D26303

To: mlaurent, dfaure
Cc: kde-frameworks-devel, LeGast00n, GB_2, michaelh, ngraham, bruns